bug#61558: 29.0.60; Indentation with c-ts-mode doesn't work in code guarded by #ifdef..#endif

[Eli Zaretskii]

To reproduce:

  emacs -Q
  C-x C-f src/dispnew.c RET
  C-u 265 M-g g
  C-e
  RET

The code around there looks like this:

static struct glyph_matrix *
new_glyph_matrix (struct glyph_pool *pool)
{
  struct glyph_matrix *result = xzalloc (sizeof *result);

#if defined GLYPH_DEBUG && defined ENABLE_CHECKING
  /* Increment number of allocated matrices.  This count is used
     to detect memory leaks.  */
  ++glyph_matrix_count;  <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
#endif

Line 265 is the one indicated with "<<<<<<".  Pressing RET goes to
column 0, not column 2 as expected.  It looks like indentation doesn't
work in code fragments that are guarded by #ifdef..#endif preprocessor
conditions.  I tried several such places, for example, lines 295, 796,
1338, 1360, 1745, 2401, 2615, and many more.

Strangely, in other places indentation does work: lines 1069, 3119.


In GNU Emacs 29.0.60 (build 326, i686-pc-mingw32) of 2023-02-16 built on
 HOME-C4E4A596F7
Repository revision: f1f571e72ae10285762d3a941e56f7c4048272af
Repository branch: emacs-29
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
System Description: Microsoft Windows XP Service Pack 3 (v5.1.0.2600)

Configured using:
 'configure -C --prefix=/d/usr --with-wide-int
 --enable-checking=yes,glyphs 'CFLAGS=-O0 -gdwarf-4 -g3''

Configured features:
ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NOTIFY
W32NOTIFY PDUMPER PNG RSVG SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XPM ZLIB

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1255

Major mode: C

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search time-date subr-x mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
c-ts-mode c-ts-common treesit cl-seq vc-git diff-mode easy-mmode vc
vc-dispatcher bug-reference byte-opt gv bytecomp byte-compile cc-mode
cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars
cc-defs cl-loaddefs cl-lib rmc iso-transl tooltip cconv eldoc paren
electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
dos-w32 ls-lisp disp-table term/w32-win w32-win w32-vars term/common-win
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar
rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock
font-lock syntax font-core term/tty-colors frame minibuffer nadvice seq
simple cl-generic indonesian philippine cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite emoji-zwj charscript charprop case-table
epa-hook jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button
loaddefs theme-loaddefs faces cus-face macroexp files window
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget keymap hashtable-print-readable backquote threads
w32notify w32 lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 80960 11004)
 (symbols 48 9604 0)
 (strings 16 28428 2568)
 (string-bytes 1 916238)
 (vectors 16 15765)
 (vector-slots 8 208391 13142)
 (floats 8 28 52)
 (intervals 40 1627 87)
 (buffers 888 11))